1. Field of the Invention
The present invention relates to an image processing device, an image capture device, an image processing method, and a program for a restoration process based on a point spread function.
2. Description of the Related Art
In an object image photographed through an image capture optical system, a so-called point spread phenomenon in which a point object has minute spread due to the influence of diffraction, aberration, or the like caused by the image capture optical system may be observed. A function representing a response to a point light source of an optical system is called a point spread function (PSF), and is known as a parameter responsible for resolution deterioration (blurring) of a photographic image.
The photographic image deteriorated in image quality due to the point spread phenomenon can be recovered in image quality through a point image restoration process based on the PSF. The point image restoration process is a process in which a deterioration characteristic (point image characteristic) caused by aberration or the like of a lens (optical system) is determined in advance, and point spread of the photographic image is cancelled through an image process using a restoration filter (recovery filter) according to the point image characteristic.
Various methods for the point image restoration process have been suggested, and for example, JP2011-10214A discloses an example of an image recovery algorithm based on the PSF. In the image recovery algorithm, a recovery filter is created on a lens side, and data to be transmitted and received between a lens and a camera is a recovery filter corresponding to a photographing parameter, whereby reduction in the amount of communication data is achieved.
JP2010-35177A discloses an image capture device which enables automatic evaluation of a photographic image. In this image capture device, image quality (exposure condition, contrast, blur, and hand-shake status) of the photographic image is automatically evaluated. In case where the remaining capacity of a recording medium is equal to or less than capacity set in advance, candidates of images to be deleted from the recording medium are determined based on the evaluation result of the recorded photographic image, and images designated by a user from among the images of the deletion candidates are deleted. The frequency of the evaluation value of the deleted image is totaled, and an image having an evaluation value with a high cumulative frequency becomes a deletion candidate with priority.
JP2011-119874A discloses a camera unit which reliably acquires image recovery information corresponding to a combination of a lens unit and a camera unit. In this camera unit, in case where lens information of a lens mounted in a camera is not retained in the camera, a transmission request of image recovery information is output from the camera to the lens, and the camera receives corresponding information from the lens.